Lifting apparatus



Jan. 24, 1961 wfs. HARTFORD ,9

LIFTING APPARATUS Filed Jan. 5, 1955 2 Sheets-Sheet 1 WILL/HM .5. Hier aea.

rramve'y Jan. 24, 1961 w. s. HARTFORD LIFTING APPARATUS 2 sheets sheet 2 Filed Jan. 5, 1955 I k izzze' WILL/HM 5: Elf/727F022),

Jim Ewe flrraelvsy deg/.6

United States Patent-O" LIFTING APPARATUS William S. Hartford, 725 W. Laurel, Colton, Calif.

Filed Jan. 3, 1955, Ser. No. 479,389

8 Claims. (Cl. 182-144) This invention relates to improved apparatus for raising and lowering a person between a ground or base level and an upper location, typically to allow performance of a predetermined work operation at the upper location. For example, a device embodying the invention may be used in grooves or orchards for allowing rapid and successive climbing of a series of trees, for trimming, picking or otherwise Working on the trees. In designing the unit, I have had in mind particularly the provision of a device adapted to be used for climbing date trees. It is also contemplated that the present devices could be used by linemen for climbing telephone poles, or by others for climbing upwardly along or within buildings or other upstanding structures.

A device embodying the invention preferably comprises a seat structure on which a user may sit, and which is adapted for vertical movement to raise and lower the person as desired. The seat structure is suspended from a flexible line arrangement, and may be actuable vertically by means of an operating mechanism, preferably power driven, carried by the seat structure. One important object of the invention is to provide apparatus of this type in which the seat structure is suspended from only one of its sides, rather than from a central location, to avoid interference by the suspending line or lines (desirably two parallel lines) with the movement of a user onto or off of the seat, and to avoid interference by the lines with relatively free movement of the user in performing the desired work operation. At the same time, this single side suspension should be such as to maintain the seat structure in a proper essentially horizontally extending condition at all times, even though the suspension is not centered with respect to the seat.

To attain proper balance of the seat, I provide a unique suspension arrangement in which the suspending line or lines are deflected laterally inwardly with respect to the seat as the line or lines extend upwardly from a main point of suspension or connection to the seat, so that a lateral force is exerted against the seat structure tending to maintain it in the desired balanced or essentially horizontal position. The lines may be thus deflected laterally by passing them about idler pulleys which are laterally offset with respect to the main point or points of connection between the lines and seat. At the latter points, the lines may be conneced to reels, about which the lines are windable to raise and lower the seat. A suitable motor may be provided for power actuating these reels.

Additional features of the invention have to do with a unique manner of detachably connecting an upper end of the suspension line or lines to a tree branch or other supporting structure, and for doing so from the ground surface or other lower location. Specifically, I may connect the lines to the upper support structure by means of a hook or other connector element, which may be carried by an elongated pole adapted to raise the hook Patented Jan. 24, 1961 from the ground surface to the desired elevation, and then hook it over a support. This pole may be longitudinally extensible from a shortened condition to a lengthened condition for use, and is desirably adapted for such extension by power operated means.

The above and other features and objects of the present invention will be better understood from the following detailed description of the typical embodiments illustrated in the accomponying drawings in which:

Fig. 1 is a perspective view of a lifting device constructed in accordance with the present invention;

Fig. 2 is an enlarged fragmentary side view of the apparatus shown in Fig. 1;

Fig. 3 is a fragmentary front view of the apparatus;

Fig. 4 is a substantially horizontal section taken on line 44 of Fig. 2;

Fig. 5 is a fragmentary section taken on line 5-5 of Fig. 4;

Fig. 6 is an enlarged fragmentary view of the upper hook element utilized in Fig. 1;

Fig. 7 is a fragmentary vertical section taken on line 77 of Fig. 3;

Fig. 8 is a view of a second form of upper hook element usable in the place of the Fig. 6 hook device;

Figs. 9 and 10 are fragmentary axial sections through two diiferent types of poles which may be used for connecting the hook elements to a tree or other supporting structure; and

Fig. 11 is a fragmentary vertical section through a track riding structure which may be utilized for suspending the lifting apparatus in place of the hooks shown in Figs. 6 and 8.

Referring first to Fig. l, I have there shown a device 10 constructed in accordance with the present invention, for raising and lowering a person between a ground or base level and an upper elevated location. More particularly, this apparatus may be utilized for raising a person 11 to an upper location alongside a tree 12, typically represented as a date tree, from which it is desired to pickthe fruit. The apparatus 10 includes an upper hook element 13, which is adapted to be hooked about a laterally projecting branch 14 of the tree, and which suspends a seat structure 15 by means of a pair of downwardly projecting flexible suspension lines 16. The hook 13 may be attached to or detached from branch 14 by means of an elongated pole 17, which carries hook 13 at its upper end, and is adapted to be manipulated from the ground surface by a user of the apparatus. It will of course be understood that the hook 13 may be connected to other types of supporting structures other than the typically illustrated tree branch. For instance, the book may be connected to the cross-arm of a telephone pole or to an elevated portion of a building, wall, or any other suitable type of support.

As seen best in Fig. 6, hook 13 may be formed of a single elongated rigid rod or member, whose upper end portion is deformed to the illustrated hook shaped configuration, and which forms a loop at 18 to which there is connected a link 19 for attachment to suspension lines 16. The rod forming hook 13 extends downwardly beyond the location of loop 18, typically being deflected laterally at 20 to avoid interference with the link carried suspending parts. The lower end of hook element 13 is connected into an upper tubular section 21 of pole 17, and may be welded to that pole section at 22.

Pole 17 may be of the extensible construction fragmentarily represented in Fig. 9. In particular, the pole 17 may be formed of a number of elongated tubular sections 21, which are telescopically receivable one within the other, and are adapted to be pneumatically or hydrau l icall y extended from a contracted or shortened normal condition to the relatively extended or lengthened Fig. 1 condition for use. At the lower end of each section 21 (except the bottom one of these sections), there may be formed a piston 23, which is actuable. upwardly, by pressure. fluid within the tubular next lower section 21 (see Big. 9). Pressure fluid for actuating the telescopic pole 1,7 to its extended Fig. 1 condition maybe introduced into the pottom of the lowermost section 21 through a line 24, leading from a suitable source of pressure fluid. At the upper end of' each of the sections 21 (except at the top section), there is provided an annular guiding and retaining cap 25, for guiding the telescopic sections for their desired relative movement, and to retain the sections against, complete separation.

Fig. 10 shows a variational form of pole, which may be utilized in place of the pole in Fig. 9. In the Fig. 10 arrangement, the various tubular pole sections 21a are completely separable by hand, to permit formation of a relatively long pole for use, and at the same time allowing. the, pole to be broken down into a number of short sections for carrying. Each of these section 21a (except the topsection), hasanupper annularly expanded tubular portion 27 which is adaptedto removably receive and hold thev lowermost,- portion of an adjacent section in the assembled condition of the pole. The hook element 13a isof course. connected into the uppermost one of. the pole sections 21a.

I With reference now to Figs. 2 and 3, the two parallel flexible lines 16 are attached to hook carried link 19 hymeans of:a horizontally extending channel member 28. This member is centrally connected at 29 to the lower end of linkv 18 for relative swinging or adjusting movement about. a horizontalaxis 39. At opposite sides; of 1inkf19, channel member- 28 carries a pair of depending rotatable sheave or pulley members 31 about which the upper end portions of the two lines 16 are. connected. Each of the lines 16 may extend upwardly about a corresponding one ofthe pulleys 31, and then 'extend' down: wardly to a point of connection 32 to the same line. Thus, the pivotally mounted channel member 28 and the pivotally carried pulley members 31 form essentially a pair. of universal connections between link 19 and lines 16;

The seat structure comprisesa horizontally extend= ing seat member on which the personll sits when the apparatus is in use. Seat 33 is rigidly carried' by a rigid frame 34, which is formed of tubular material; bent to the configuration illustrated in the drawings. More specifically, the tubular material forming frame 34 may extendhorizontally beneath seat 33,at 35 and then upwardly as a pair of parallel upwardly extending tubes 36 at a forward side of the seat structure. Thesetwo verti cally extending tubes 36 may be interconnected by a return bend at 37 at their upper ends. Beneath the seat carrying portions 35 of the tubular material forming frame 34, the two tubes may be doubled back and then forwardly at 39for connection to the vertically extending tubes 36 at 40.

The upstanding tube members 36 carry a body member 41 to which certain of the moving parts of the apparatus are mounted. This body member preferably carries a pair of spaced axially alined reels 42, about which lines 1f6-respectively are .windable to raise and lower seat structure 15 and the carried person. Reels 40 are mountedto frame 34 for rotation about a common horizontal axis, and are adapted to be driven in either of, twoopposite directions by a motor 43 typically mounted to'body'41, at av location about the reels. Motor 43 bas a down wardly projecting driven shaft 44 having a single thread, worm portion 45 engaging and driving a worrrrgear -46 which drives. ashaft 47 connected at its;opposite eagle; to reels 42. Motor 43 is adapted to be driven in a 4 direction for either winding or unwinding lines 16 on reels 42.

The motor 43 may typically be an electric motor, adapted to be driven by power supplied to the motor through a supply line 48. The motor is controllable by the person 11 operating the device, as by actuation of a control unit 49, typically having a push button 50 for energizing the motor to wind lines 16 on reels 42, and a second button 51 for reversely energizing the motor to unwind the lines. It is contemplated that, if desired, motor 43 may be driven by batteries 52 carried on frame 34 beneath seat 33. Also, it is contemplated that motor 43 may be of' a pneumatically or hydraulically driven type, rather than an electrically operated type, in which case suitable pressure fluid supply lines would be substituted for electric line 48-, and in which case the control unit 49 would comprise a controlling valve structure rather than a switch mechanism.

For retaining the wound portions of lines 16 in a tightened condition on reels 42, and for facilitating proper winding of the lines on the reels, there may be provided a roller; 53 bearing upwardly or laterally inwardly. against. the line wound' on each reel, to holdit in. proper position. Each of these rollers 53 may berotatably. carried by an arm 54 pivotally attached to body 41 at 55, and yieldingly urged upwardly by a spring 56 to cause theroller 53 to bear upwardly against the wound line.

In extending upwardly from reels 42 to the upper hook structure, the two flexible suspension lines 16 extend past and: movably engage a pair of guide pulleys 57, which; are mounted for rotation about essentially a common axis; These two pulleys 57 are movably carried by a common vertically adjustable mounting structure 58, which ineludes an essentially vertically extending sheet metal elemeat 59 bearing against a first side of vertical frame elemerits-.36, and a pair of 'vertically spaced clampingmerm bers 60 for engaging the opposite side offrame elements 36: The two opposite edge portions-61 of element 59-are turned inwardlyin conformanceto the curvature of -tubu lar frame elements 36, to embrace those elements and retain element 59 against relative lateral displacement; Element 59 carries a pairof vertically spaced threaded studs- 62, which extend through openings in clamping members 60', and onto which are connected a pair-of nuts 63for 'tighteningmembers 60 toward element 59 and thereby securing'carrier structure 59 in fixed relation to frameelemcnts 36. As wil be understood, by loosening nuts. 63-it is-possible-to allow vertical adjusting move: mentor elements 59 and 60 along frame elements36 to thus vertically adjust pulleys 57.

At a side of element 59 facing awayfrom the tubular frame members 36, element 59 rigidly carries a U-shaped bracket member 64, to which is mounted an essentially verticallyextending screw or hinge pin 65. This pin 65 acts asashaft for pivotally mounting a horizontally extending member 66, for pivotal movement about the es: sentially vertical axis of pin 65. To the opposite ends of member 66 thereare mounted by hinge pins 67 a pair of U-shaped-carrier elements 68 to which pulleys 57 respectively are rotatably mounted by horizontal axle elements 69. Hinge pins 67 mount pulleys 57 and their carrier elements 68 for pivotal movement about the cs5 sentially. vertical'axes 70 of'pins 67, so that the pulleys 571 are free for adjusting movement about pin 65' and pins 67 to follow=the adjusting movement of suspension lines 16;

In using-the apparatus of Fig. 1', an operator first extends po1e17 to a length for reaching the elevated tree branch 14..or-other.supporting structure, and then manipu-v Theeuser then sitsion seat 33, and .then pushes the-button- 15.to energize motor, 43 :..in a. directi on for raising seat structure 15 and the carried person upwardly. More specifically, su'ch energization of motor 43 drives reels 42 in a direction for winding lines 16 on the reels and thus causing the seat structure and carried person to raise upwardly toward the point of suspension 14. When a desired elevated position is reached, the operator releases push button 50 to stop the raising operation. In this condition, the worm gear type of drive 45 and 46 acts as an automatic brake for holding the apparatus in its elevated condition. The user may then perform the desired date picking or other work operation at the elevated location, following which the apparatus may be lowered by pushing button 51 to reverse drive motor 43 and reels 42. After the seat structure has reached the ground level again, the user may remove hook 43 from branch 14 and may then carry the apparatus to the next successive tree for repeating the operation.

An important feature of the apparatus resides in the fact that the seat structure 15 is supported from only one of its sides, and yet in spite of that fact the seat 33 is always maintained in a substantially horizontal condition. The center of gravity of seat structure 15 and the carried person 11, when the apparatus is suspended from lines 16, is offset considerably to the left of reels 42, pulleys 57 and suspension lines 16, as the apparatus is seen in Fig. 2. This offsetting of the center of gravity laterally from the suspension means would of course normally tend to cause the seat structure to swing to a condition in which seat element 33 was no longer horizontal. Such swinging of the seat structure to a non-horizontal position is prevented by mounting of reels 42 and pulleys 57 in the unique laterally offset relation shown in Fig. 2. Specifically, pulleys 57 are so positioned as to deflect lines 16 laterally as they extend upwardly from reels 42 toward the upper suspension location. This deflection of the lines is in a direction laterally toward the location of the user 11 and the seat on which he is positioned. That is, the lines 16, are deflected inwardly of the seat structure in a direction the reverse of the direction in which the lines, reels and pulleys are all offset as a unit with respect to the center of gravity of the apparatus. With particular reference to Fig. 2, all of the suspension parts are offset to the right of the center of gravity as seen in the figure, while the direction in which pulleys 57 deflect lines 16 as they extend upwardly is the reverse of that direction of offset, or to the left. It has been found that this arrangement causes the exertion of a lateral force against pulleys 57 (to the right as seen in Fig. 2), which counteracts the normal tendency for seat 33 to swing downwardly, and thus maintains seat 33 in substantially horizontal position at all times. It is also highly desirable that the lines 16 be wound about reels 42 in the particular direction shown in Fig. 2.

Fig. 8 shows a variational form of hook structure which may be substituted for that shown in Fig. 6. This Fig. 8 arrangement comprises a sheet metal carrier member 71 to which a pair of opposed hook elements 72 are pivotally attached at 73. These hook elements are capable of swinging between the illustrated full line opened condition and a closed condition represented in broken lines in Fig. 8, both hooks being receivable about a branch or other supporting element in the broken line positions. Plate 71 is attached by a rod 75 to the upper end of a pole such as that shown at 17 in Fig. l, to be connectible to a supporting structure 14 by manipulation of the pole from the ground surface. Hook elements 72 extend downwardly beyond their point of pivotal connection 73, to form lower end portions connectible at 76 to a pair of pulleys or sheaves 77, to which the upper ends of lines 16a corresponding to lines 16 of Fig. 1 are attached. As will be appreciated, when the hooks of Fig. 8 are received about a supporting branch or structure, the downward pull exerted on lines 16a by the supported seat structure tends to relatively close hooks 72, to at all times insure positive connection of the hook elements to the branch or other supporting member.

Fig. 11 shows a still further form of upper c'onne'ctor unit to be substituted for the hook 13 of Fig. 6, where desired. This Fig. 11 arrangement is utilized where it is possible to permanently install a horizontal supporting track 78, on which the rollers 79 of a track riding carrier member 80 are receivable. In this Fig. 11 arrangement, a link 19b is pivotally connected at 81 to the body of track riding structure 80, and pivotally supports the seat structure through parts 28b, 31b, and 16b corresponding to the parts 28, 31 and 16 of Fig. 3.

I claim:

1. Apparatus comprising a carrier structure on which a load may be supported and adapted to be moved vertically to raise and lower the load, a connector unit adapted to be connected to an upper support structure for suspending said carrier structure therefrom, two flexible lines connected at their upper ends to said connector unit and extending downwardly therefrom essentially parallel to one another and connected at their lower ends to said carrier structure to suspend the latter from said connector unit, said carrier structure including a vertically movable body having an upstanding projection at the location of said lines and having a load carrying portion extending laterally in a predetermined direction from a lower portion of said projection and suspended thereby as a cantilever, said load carrying portion having a platform for receiving the load at a location such that its center of gravity is offset laterally from said projection and is offset laterally in said predetermined direction beyond the main upper suspending portions of said lines, two pulleys engaging and guiding said lines respectively as they extend downwardly, means mounting said pulleys to said projection at a level higher than but offset laterally from said platform and each for rotation about a generally horizontal axis, said lines engaging said pulleys re spectively at a side facing laterally in the direction of said load receiving platform, and said lines then extending angularly downwardly and laterally away from the load platform, and motor driven reel means carried by said body and acting to wind and unwind the lower portions of said lines to raise and lower the carrier structure.

2. Apparatus as recited in claim 1, in which said reel means turn about an essentially horizontal axis generally parallel to the axes of said pulleys and are located at the lower end of said angularly downwardly and forwardly extending portions of the lines.

3. Apparatus as recited in claim 1, in which said reel means include a reel associated with and winding each line and power driven about a generally horizontal axis, each line first engaging said reel at its side which is closest to said platform, to then pass about the bottom of the reel and up its opposite side.

4. Apparatus as recited in claim 1, in which said pulley mounting means include means mounting the two pulleys for bodily horizontal swinging movement relative to said projection and relative to each other, and in addition to rotary movement of the pulleys.

5. Apparatus as recited in claim 1, in which said connector unit includes two elements connected to and suspending upper ends of said lines respectively, a transverse member suspending said two elements and pivotally connected at two horizontally spaced locations thereto, and an additional member suspending said transverse member and pivotally connected thereto between said two spaced locations.

6. Apparatus as recited in claim 5, in which said pulley mounting means include means mounting the two pulleys for bodily horizontal swinging movement relative to said projection and relative to each other, and in addition to rotary movement of the pulleys.

7. Apparatus as recited in claim 4, in which said pulley mounting means include a part mounted to an upper portion of said projection for swinging movement about a generally vertical axis, and means mounting said 7 zpul-leys to said part at two horizontally spaced locations and for individual swinging movement about two generally vertical axes, in addition to the rotary movement of the pulleys.

8. Apparatus as recited in claim 1, in which said pulley mounting means include a part mounted to an iupper portion of said projection for swinging movement about a generally vertical axis, and means mounting ,said pulleys to said part at two horizontally spaced locations and for individual swinging movement about two generally vertical axes, in addition to the rotary moveinent of the pulleys.

- References iCited :in the :file of this patent UNITED STATES 'PATENTS C rockett .May 16, Gadsby Feb. .2, lNordenborg .June 1, Weeks May 11, Bates v Aug. .17, Kolvoord Feb. 7, ,Biebel .Mar. 2, Riblet Mar. 5, Green Sept. 21, 

